Gas turbine engines, particularly those in military applications, are known to include exhaust modules having an augmentor (also commonly referred to as an “afterburner”) and a variable area nozzle (VAN). During operation of such engines, gas passes downstream of the turbine, expands, and loses temperature. The augmentor injects fuel downstream of the turbine to reheat the gas. In conjunction with the added heat, the pressure rises in the augmentor and the gas is ejected through the variable area nozzle at a relatively high velocity.
One known type of variable area nozzle includes a translatable synchronization ring coupled to a plurality of moveable flaps via one or more linkages. The synchronization ring is moveable in response to a plurality of actuators. In the example, the actuators are connected a common motive fluid source. Fluid is provided to each of the actuators in parallel to bring about a desired movement of the translatable synchronization ring and, in turn, the flaps.
Another known type of variable area nozzle includes a plurality of linear actuators disposed circumferentially about a synchronization ring. Each of the linear actuators is in communication with a control unit, which is configured to provide instructions to the linear actuators to adjust the position of the synchronization ring.